Appleton-Whittell Research Ranch

Pre white-settlement fires created an annually shifting patchwork of re-sprouting and mature grasses throughout the area. The specific impacts within any burn patch depended on soils; species present; winds; precipitation and temperatures before, during, and after burns; season and frequency of the fires; fuel accumulation; etc. Without periodic fires, southeast Arizona's grasslands might never have established, or would have succeeded to shrubland (dominated by woody plants) or other communities, centuries ago.

Most areas were naturally ignited every five to twenty years, on average. Mesas probably burned more often, while canyons and riparian areas probably burned less often (these estimates are based on the annual rings of pine trees in surrounding mountains, as the oak trees associated with grasslands produce very indistinguishable annual rings). Given fire suppression throughout the past 100 years, many unburned grasslands in this area have become shrub savanna or mesquite woodlands and their grassland wildlife has been replaced by species adapted to the more dense and woody habitats.

The most desirable fire would be ignited by lightning, burn 10 - 1,000 acres in an area on which we have tremendous data, be extinguished by rain, and we would learn about it after it is out and while we are sipping our morning coffee. The most undesirable fire would be ignited by a cigarette or arsonist at the driest time of year, would hot burn 4,000 acres, and might threaten or destroy houses, fences, and infrastructure. This was the case with the Ryan Wildfire.

Planned fires such are carried out only under a set of strict conditions, called the fire prescription, which incorporates the type of fuel, the topography of the land, the relative moisture of the air, the wind direction, wind speed, and other factors. Prescribed ignition allows us to minimize human manipulation of The Research Ranch by restoring the historic fire frequency rather than continue a one-sided (suppression only) intervention. It actually reduces the risk of wildfire by reducing fuel loads (accumulated dry material) in problematic areas.

Maintain fire adapted natural communities by assuring an historic frequency of prescribed fires that mimics the historic natural wildfires, which occurred prior to Anglo settlement.
Reduce the potential for accidental or arson wildfires during the driest time of year when the fire might burn hotter than desired and would be hardest to contain.
Prevent loss of buildings, vehicles, and infrastructure.
Prevent fire spreading into cottonwood and willow riparian areas.
Create a patchy post-fire mosaic within burn units as well as between burn units. A vegetative mosaic can be maintained by varying intensity, frequency, and season of burn within each fire. This should minimize wildlife losses to fire, and should stimulate the native grasses and forbs, on which our wildlife depends.
Reduce the fuel load in risky areas (bordering houses or riparian areas).
Inflict minimum disruption to the land surface during the fire management operation. Vehicles should remain on designated roads wherever possible to minimize unnecessary habitat damage.

After decades of suppression, the naturally renewing force of fire has returned to the Research Ranch. The Ryan Wildfire superceded our prescribed burn plan by burning 7200 acres on April 30, 2002. Now that fire has returned to the land on a large scale, the Research Ranch will continue the prescribed burn plan under the historic fire regime.